How Missouri's Helmet Laws Can Affect Your Motorcycle Accident Claim

 

A man I know was riding his motorcycle on Highway 65 outside Springfield when a pickup truck crossed the center line and hit him head-on. He wasn’t wearing a helmet. He was 26, had been riding for four years, and had made the same choice plenty of times before without incident.

 

He survived. He had a traumatic brain injury, a fractured collarbone, and a road rash that required skin grafting on his left arm and leg. The other driver was clearly at fault. The truck’s dashcam showed the lane departure plainly.

 

His attorney called a week into the case with a specific concern. Missouri’s comparative fault rules meant the defense was going to argue that his decision not to wear a helmet contributed to the severity of his head injury. And they were right that it was an argument available to them.

 

That argument didn’t end his case. It shaped it in ways that took a year and significant medical expert work to address.

 

Missouri’s Helmet Law and Who It Covers

 

Missouri requires helmets for motorcycle riders and passengers who are 25 years old or younger. Riders 26 and older are not legally required to wear one.

 

The man from Highway 65 was 26. He broke no law by riding without a helmet. That matters for the criminal side of things. It matters less in civil litigation than most people assume.

 

Missouri uses pure comparative fault. If you’re found partially responsible for your own injuries, your recovery gets reduced by your percentage of fault. There’s no cutoff. Even a plaintiff found 80% responsible can technically recover 20% of their damages.

 

The defense in a motorcycle accident case involving a helmetless rider doesn’t argue you broke the law. They argue that your choice not to wear a helmet contributed to the severity of your head injuries, regardless of whether the law required you to wear one. That argument affects the fault percentage assigned to you, which directly affects what you recover.

 

The National Highway Traffic Safety Administration’s motorcycle safety resources document extensively what helmets do and don’t prevent. Helmets are highly effective at reducing traumatic brain injury severity and fatality in motorcycle crashes. NHTSA estimates that helmets saved approximately 1,872 motorcyclist lives in 2017 alone, and that an additional 749 lives could have been saved if all motorcyclists had worn helmets.

 

That data cuts both ways in a personal injury case.

 

It gives the defense expert something to work with. If helmets reduce TBI severity, and you weren’t wearing one, the defense argues that some portion of your head injury is attributable to your own choice. In a case where the TBI is the most significant and most expensive injury, that argument can substantially affect the damages calculation.

 

It also gives the plaintiff’s expert something to work with. The same research that documents helmet effectiveness documents what helmets don’t protect. Road rash. Orthopedic injuries. Internal injuries. Spinal injuries. Anything from the shoulders down that a helmet plays no role in preventing. A defense that focuses on the TBI can’t extend that argument to every other injury the crash produced.

 

The medical expert work in these cases is specifically about separating the damages. What injuries would have been the same regardless of helmet use. What injuries might have been less severe with a helmet. Building that distinction with credible medical testimony is how you contain the comparative fault percentage rather than letting the defense assign you responsibility for everything.

 

The Comparative Fault Calculation in Practice

 

The man’s attorney retained a neurologist and a biomechanical engineer. Their testimony addressed two specific questions. First, what was the mechanism of the TBI given the force of the collision and the angle of impact. Second, whether a helmet of the type the rider would realistically have worn would have mitigated the TBI given those specific forces.

 

Helmets have their limits. A frontal collision at highway speed produces forces that exceed the protective capacity of most consumer-grade helmets. The biomechanical engineer’s analysis addressed whether the specific crash dynamics meant the TBI was likely regardless of helmet use, given the nature of the impact.

 

That’s a different argument than the defense’s general claim that helmets reduce TBI severity. It’s a specific argument about this crash, this impact, and this injury. Specific arguments are harder to dismiss than general ones.

 

The defense’s comparative fault argument survived to trial but the jury found the rider 15% at fault rather than the 40% the defense had been pushing for. The difference between 15% and 40% in a case with serious damages runs to tens of thousands of dollars.

 

Head Injuries and Helmet Use Aren’t the Only Issue

 

Defense attorneys in Missouri motorcycle cases sometimes try to extend the helmet argument beyond head injuries, arguing that a helmetless rider was demonstrating a general disregard for safety that should factor into the fault analysis broadly.

 

This argument doesn’t have strong legal support in Missouri. The comparative fault analysis is supposed to be specific to the conduct that contributed to the particular injury, not a general character assessment. A plaintiff’s attorney who objects to this framing effectively and who has experts who can address the injury-specific analysis usually contains this argument.

 

What the defense can legitimately argue is that failing to take reasonable precautions contributed to the severity of specific injuries. What they can’t legitimately argue is that one protective equipment choice makes the rider responsible for injuries that have nothing to do with head protection.

 

A broken pelvis has nothing to do with whether someone was wearing a helmet. Neither does a ruptured spleen. Neither does road rash on the legs. These damages categories are insulated from the helmet argument if someone makes that point clearly and early.

 

Gear Beyond the Helmet

 

Motorcycle gear other than helmets doesn’t carry the same legal weight as the helmet question in Missouri but it can appear in the case.

 

Gloves, jackets, boots, and pants designed for riding reduce the severity of road rash and extremity injuries. Missouri has no law requiring any of this gear. A rider in shorts and a t-shirt who suffers severe road rash is going to face some version of the argument that their clothing choices contributed to the severity of those injuries.

 

The counter to this argument follows the same logic as the helmet argument. What injuries would have been the same regardless of gear. What injuries the specific gear would have reduced. A defense argument that riding clothes would have reduced road rash severity is different from a defense argument that riding clothes would have prevented the broken bones, the internal injuries, or the spinal damage.

 

Document what you were wearing at the time of the accident. Photographs taken at the scene or at the hospital are evidence. If you were wearing riding gear and it’s damaged or destroyed in the crash, preserve what you can. These details matter in establishing the context of your gear choices.

 

Liability in motorcycle cases is sometimes disputed in ways that car accident cases aren’t.

 

Biases against motorcyclists exist in the general population and they show up in juries. The perception that motorcycle riding is inherently risky and that riders accept that risk is a background assumption that defense attorneys exploit in every case involving a motorcyclist, not just cases involving helmet use.

 

Building a case that counters this bias requires documenting the at-fault party’s conduct thoroughly and building a factual record that makes clear what actually caused the crash. In the Highway 65 case, the dashcam footage showing the truck’s lane departure was the most important single piece of evidence in establishing that the rider did nothing to cause the accident, regardless of what he was or wasn’t wearing when it happened.

 

Get legal help before you make any decisions about statements, recorded interviews with insurers, or anything related to the helmet question.

 

A motorcycle accident attorney in Missouri with specific experience in comparative fault cases understands how to retain the right medical and biomechanical experts, how to build the injury-specific analysis that contains the helmet argument’s impact on the damages calculation, and how to address juror bias against motorcyclists before it affects the verdict. You can review a Super Lawyers profile for background on the firm’s recognition and practice areas before reaching out.

 

The man from Highway 65 eventually recovered a meaningful amount. Less than his case would have been worth if he’d been wearing a helmet. More than the defense’s 40% fault argument would have left him with.

 

His choice not to wear a helmet was legal. It affected his case. It didn’t end it.

 

Those three things can all be true at the same time, and understanding how they interact before the insurer starts building their version of the story is the practical advantage available to anyone in this situation.